Vibrohammer



United States Patent Inventors Czeslaw Winceuty Gawlik Gdynia, Grottgera; Dionizy Simson, Gdansk, Stryjewskiego, Poland Appl. No. 778,514 Filed Nov. 25, 1968 Patented Dec. 29, 1970 Assignee Zaklady Remontu Maszyn Budowlanych Nrz Gdansk, Siennicka, Poland Priority Dec. 12, 1967 Poland P-l24,044

VIBROHAMMER 8 Claims, 9 Drawing Figs.

US. Cl 173/131, 173/49, 173/139 Int. Cl E02d 7/06, B06b l/ l6 Field of Search 1 73/49 Primary ExaminerErnest R. Purser Atmmey-Stevens, Davis, Miller & Mosher ABSTRACT: A vibrohammer used for driving and also removing piles, bulkheads and similar elements from ground including ringshaped elastic links of variable profile which absorb the transverse and torsional vibrations of the anvil, bolt of tapered ends mounted in the holes of the anvil by means of expanded sleeves eliminating superfluous backlashes between bolts and holes of the anvil. Moreover, the said vibrohammer includes the wedge with longitudinal and transverse grooves connecting the grip of driven element with the anvil, springs, shaped conically and clamped preliminary by weight of vibrator, working on tension, as well as suspension gear, a rope of which is engaged below and above of center of gravity vibrohammer.

PATENTED BEBZS I970 SHEET 2 OF 4 VIBROHAMMER This invention relates to a vibrohammer used for driving in and extracting piles or similar elements from the ground etc. The vibrator hammer is connected to an anvil by means of at least two springs.

Vibrohammers in production to date have had numerous disadvantages resulting from the poor construction of some of their assemblies, which cause a lot of difficulties during work and servicing of the Vibrohammers, as well as an early wearout of their individual parts and assemblies.

One assembly is a spring link which is meant to protect the body of the regulator of the vibrohammer from the vibrations produced by the anvil when it is struck by the ram of. the vibrohammer during operation.

Previous spring links were made of elastic materials, such as rubber rings, which were supported on the front surface of the body of the regulator, and were fastened to this body by means of nuts screwed on threaded portions of the anvil.

In present construction, where anvil vibration is a problem, the body of the regulator is mounted on the anvil by means of slip rings, and is protected from torsional vibrations with a wedge or a roller inserted into slides mounted on the anvil.

Such spring links absorb only longitudihal vibrations, while transverse and torsional vibrations are transmitted to the body of the regulator without any absorption at all. This is the cause of the fast wearing out of the metal parts and has an adverse influence on the work of the other assemblies of the vibrohammer which are mounted on this body.

The next detail, which improves the technical value of the vibrohammer, is a bolt mounted in the anvil of the machine. Each blow of the ram is taken by this bolt and transmitted through the'anvil to the element being worked. Some known types of vibrohammers have rams with oval holes around bolts which are mounted in the anvils. These bolts are subjected to blows by the rams in various directions along the vertical plane. I I

According to the use of the vibrohammer for driving in or extracting operations, cylindrical bolts are used which are forced into the anvil holes with a moderate pressure. In spite of accurate fills between the bolt and the holes, such design has this unfavorable feature, namely, the bolt becomes loose from repeated blows of the ram and consequently causes an early wearout of the surfaces of the holes and the bolt itself.

Besides the above-mentioned fact, wherever a cylindershaped bolt is used, the hole in the ram must have its surface properly shaped in order to ensure a correct contact between this ram surface and the bolt. Preparation of such holes in the ram requires much highly skilled labor and special tools. Further details of the vibrohammer, exposed to early wear, are a wedge fastening the grip to the anvil and the protection of this wedge from getting loose.

All known protecting systems of wedges in the vibrohammer are limited to various safety pins, or split pins, driven across the wedge and adequately secured to prevent loss. The wedge could also be protected by a thrust plate which is supported on and secured to the anvil by a screw driven into the front side of its thinner end. Corrective operation of the screw ensures tight positioning of the wedge.

Such protections, even when secured by a similar device, become loose after a relatively short time and consequently cause early wearout of the wedge together with its safety pins.

Springs are particularly sensitive elements of the vibrohammer because various stresses are generated along the longitudinal axis of the springs, by vibrations of the machine and its sideways motions.

Until recent years the springs were mounted, after being preliminarily compressed, so as to be operated throughout their entire range as compressed springs. This caused increased accumulation of stresses during operation of the machine and was the main cause of the springs breaking because much of the stress was concentrated near spring mounting points.

Vibrohammers to date were suspended on steel cables hung from a hook on the crane. The cables were wound around dogs mounted on the body of the regulator near the center of gravity of the machine.

Such suspension gave satisfactory results for driving elements into the ground, but was rather uneconomical for removing such elements from" the ground. The crane, due to the possible damage which could be done to a body of the regulator, removed only the vibrohammer together with the removed element. This did not produce any remarkable speed in the operation, and the lifting capacity of the crane was only partly exploited.

In order to avoid such an uneconomical situations, it was necessary to provide such simple assemblies of the vibrohammer, as a spring link, a bolt and the manner of its assembly in the anvil, a wedge together with its safety devices, and cables, which would absorb longitudinal, transverse, and torsional vibrations, and a device to protect the wedge from creeping out under influence of the vibrating anvil. The suspension cables should be located at such a point in the vibrohammer that the machine suspended from these cables will maintain a vertical position, and during the pile-extracting operation full power of the crane can be utilized.

It is an object of this invention to prove the above by means of a spring link shaped in .the form of a ring with beads. Recesses were cut in the body of the regulator and portions of the anvil were flattened. The link beads were located in these recesses and on the flat spots while the ring of the link is located in a seat of the body of the regulator and compressed with flanged nuts.

The bolt is mounted in expanding sleeves, slid on tapered ends of the bolts, under the pressure of a screw located in the bolt. The wedge is firmly held by means of one or two toothed lock plates fastened to the wedge by means of a screw. These lock plates are connected to the wedge in such a way that the I screw is free from the force of inertia of the lock plates. The wedge has transverse grooves and recesses cut along its length. These grooves match teeth in the lock plates, and their rims bear against outside walls of the recesses.

Another feature of the machine is that the cable is introduced to the machine below its center of gravity, and the center of gravity is held by a clamp mounted on the body of the regulator.

Such a combination of means has led to such technical advantages as good absorption of longitudinal, transverse, and torsional vibrations of the anvil, apart from eliminating friction between the contacting surfaces of the anvil and the body of the regulator, because these parts of the machine are joined together through an elastic material of the link whereby direct contact between these surfaces is eliminated.

Assembly of the expanding sleeves on the tapered ends of the bolt, and nuts on the bolt, removes any gaps between the bolt and the holes in the anvil, since the nuts will compress the expansion sleeves to force them on the tapered ends of the bolts to fill even the smallest gap.

Protection against the loosening of the wedge is effected by lock plates clamping the wedge and a screw free from forces of inertia generated by the lock plates. It protects the screw from breakage and ensures a durable connection of the anvil and the grip. If by chance the wedge gets loose, it can easily be tightened by resetting the lock plates and refastening them to the wedge.

Cables which are joined below the center of gravity with clamps to keep the cables inside the center of gravity produced a technical effect in the form of utilization of the full lifting capacity of the crane and consequently accelerated pulling of the elements out of the ground.

The invention discussed above is shown, for example, in the following drawings in which:

FIG. 1 is shown from a front view in partial vertical section;

FIG. 2 is a perspective view of a spring link, also partially in section;

FIG. 3 is a cross section of the vibrohammer taken along line 3-3 of FIG. 1;

FIG. 4 is an exploded perspective view of the lock plates;

FIG. 5 is schematic front view of the machine suspended on cables introduced through clamps,

FIG. 6 is the vibrohammer of FIG. 5 in side view;

FIG. 7 is a front view of the same machine seen with cable put around a dog mounted in the bottom portion of the body of the regulator;

FIG. 8 shows the cable in its clamp; and

FIG. 9 shows the cable dog with a safety plate securing the cable in place.

As can be seen from FIGS. 19, the vibrohammer consists of a vibrator 1 with a ram 2, anvil 3, body of the regulator 4, and a grip 6. The vibrator is mounted on springs 7 fastened to the body of the regulator. The regulator is fixed to the anvil by means of spring links 8 formed in the shape of rings with beads 9. The body of the regulator has seats 10 and recesses 11, in which the spring link is mounted. The anvil has flats 12 which bear upon beads of the spring link.

The spring links exert pressure upon seats 10 through nuts 13 equipped with flanges 14. The seats 10 and flanges 14 are shaped in such a way that they embrace ring 8 of the spring link on its outside and inside diameters and compress it between themselves as a result of tightening the nuts 13. The body of the thus mounted regulator has no direct contact with the anvil 3, but is at the same time connected to it.

Longitudinal and transverse vibrations are absorbed by the elastic material of the ring 8, while torsional vibrations are absorbed by elastic material of beads 9. In both holes of the anvi]. there is a bolt 15 mounted with a hole drilled along its longitudinal axis. Both ends of the bolt are formed in the shape of a tapered frustum inserted into expanding sleeves 16 which fix the bolt in the anvil holes. A screw 17 is fitted inside the bolt. When nuts 18 are tightened, the expanding sleeves are forced on the tapered ends of the bolt to fill even the smallest gap due to pressure of the screw 17. Owing to tapered ends of the bolt, the surfaces in the holes of the ram can be straight, because regardless of position of the ram, this surface will have a close and proper contact with the bolt.

A wedge I9 fastening the grip to the anvil is inserted into the anvil. This wedge has recesses 20 cut along its longitudinal axis and grooves 21 cut across and between these recesses. There is also an oblong hole 22 parallel to these recesses. The wedge has one or two lock plates 23 with teeth out on their surfaces to engage the grooves cut on the wedge. A round hole for screw 24, when inserted through an oblong hole 22 in the wedge, holds the lock plate, or plates, firmly on the wedge.

The length of the lock plates is exactly the same as the distance between the two extreme walls of the recesses. Due to this fact the lock plates, after locating the wedge, are firmly held between these walls. This system of the wedge with its lock plates prevents the wedge from creeping out of the hole and removes all forces from screw 24, due to inertia of the lock plates generated during operation of the vibrohammer. Because these plates are engaged by grooves and compressed between walls of the recesses, they have no influence on the screw. When the wedge becomes loose, its can be readily tightened by driving the wedge deeper and fixing it in its new position. It is clear that the lock plates prevent the wedge from getting out of place when the system rests on the anvil.

Above-mentioned springs 7 are fastened by their ends to the body of the regulator and to the vibrohammer. The springs may be fixed directly or indirectly, that is, through other components of the vibrohammer. As already explained, the springs 7 have different pitch diameters. The smallest diameter is directed towards the body of the regulator. Such assembly of the springs ensures that they will operate on stretching forces for both positive and negative work.

The vibrohammer, which is adapted for extracting elements The vibrohammer may also be suspended in a different way;

that is, cable 5 is wound around dogs 27 mounted in the bot-" torn portion of the body of the regulator 4 and introduced into the clamps 26. The clamps 26 and dogs 27 are equipped with straps 28 covering clamps and screens 29 c'ov'ering the bottom portion of the dogs. I Y I The vibrohammer is suspended on a cable, which is introduced through grip holes 6, and the machine is maintained in a vertical position. Thus, it can be safely used for pileremoving operations at full power of the crane, whereby the removing process is considerably shortened. When pile removal operation is performed, or when no grip 6 is used, the vibrohammer, due to the cable 5 wound around dogs 27, is kept in its vertical position.

We claim:

1. A vibrohammer comprising a vibrator, a regulating device, spring means joining said regulating device to said vibrator, an anvil, ring-type elastic links mounting said regulating device on said anvil to transmit the vibration to the element being worked, a bolt mounted in said anvil, a holder for the element being worked and a key provided with means provided for fastening a rope sling to said vibrohammer, wherein the improvement comprises said ring-type elastic link being provided with a bead, recesses formed in the regulator device, and flats formed in said anvil, said bead being secured in said recesses and flats, bolt means passing through a hole in the anvil, expansion sleeve means mounted on said bolt means to secure it in said hole, key means provided with longitudinal grooves and with transverse grooves, plates mounted in said grooves to secure the key means against loosening, and means to secure a rope of a sling supporting said vibrohammer below the center of gravity of said vibrohammer and clamping devices mounted on the body of the regulator above the center of gravity for guiding said rope.

2. A vibrohammer according to claim 1 wherein the ringtype elastic link is set in the body of the regulator device in the seat formed by a flange embracing the outer diameter of the ring and by a flanged nut embracing the inner diameter of the ring.

3. A vibrohammer according to claim 1 wherein the bolt has both ends shaped in the form of truncated cones and has a through hole along its axis.

4. A vibrohammer according to claim 3 wherein the conically shaped bolt ends are mounted in said expansion sleeves which fix the bolt in the hole in the anvil due to pushing of these expansion sleeves on the cones of the bolt.

5. A vibrohammer according to claim 4 wherein pushing of said expansion sleeves on the conical bolt ends is effected by a preliminary stress imparted by a threaded shaft set in the bolt hole and nuts tightly mounted on the ends of said shaft.

6. A vibrohammer according to claim 1 further comprising plates provided with grooves which mesh with the grooves in the key, whereby after being fastened to the key with their sides meshing they are supported on the border planes of the recesses.

7. A vibrohammer according to claim 1 wherein the rope of the sling is put through holes formed in the body of the holder and hooked on catches set in the lower part of the body of the regulator and guided in clamping devices.

8. A vibrohammer according to claim 7 wherein the clamping devices are provided with straps, and the catches are provided with covers for securing the rope against accidental removal. 

